手势识别(拖动,旋转,捏合)

 09-手势识别(拖动,旋转,捏合)

    1.平移    
          UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self
                                                                      action:@selector(pan:)];
           添加手势
          [self.imageV addGestureRecognizer:pan];
          
          实现手势方法
           手指在屏幕上移动进调用
            - (void)pan:(UIPanGestureRecognizer *)pan{
                获取当前手指移动的偏移量
                CGPoint transP =  [pan translationInView:self.imageV];
                NSLog(@"%@",NSStringFromCGPoint(transP));
                Make它会清空上一次的形变.
                self.imageV.transform = CGAffineTransformMakeTranslation(transP.x, transP.y);
                
                self.imageV.transform = CGAffineTransformTranslate(self.imageV.transform, 
                                                                           transP.x, transP.y);
                复位,相对于上一次.
                [pan  setTranslation:CGPointZero inView:self.imageV];
            }

    2.旋转
          
        添加旋转手势
        UIRotationGestureRecognizer *rotation = [[UIRotationGestureRecognizer alloc] 
                                     initWithTarget:self action:@selector(rotation:)];
        设置代理,设置代理的目的就让它能够同时支持旋转跟缩放
        rotation.delegate = self;
        添加手势
        [self.imageV addGestureRecognizer:rotation];
        
        
        当旋转时调用
        - (void)rotation:(UIRotationGestureRecognizer *)rotation{
            旋转也是相对于上一次
            self.imageV.transform = CGAffineTransformRotate(self.imageV.transform, 
                                                                 rotation.rotation);
            设置代理,设置代理的目的就让它能够同时支持旋转跟缩放
            rotation.delegate = self;
            也要做复位操作
            rotation.rotation = 0;
        }
    
    3.添加缩放手势
        添加缩放手势
        UIPinchGestureRecognizer *pinch = [[UIPinchGestureRecognizer alloc]                                             initWithTarget:self action:@selector(pinch:)];
        
       [self.imageV addGestureRecognizer:pinch];

        
        缩放手势时调用
        -(void)pinch:(UIPinchGestureRecognizer *)pinch{
            平移也是相对于上一次
            self.imageV.transform = CGAffineTransformScale(self.imageV.transform, pinch.scale, 
                                                                                  pinch.scale);
            复位
            pinch.scale = 1;
        }